Method of treating vulcanized fiber



sugar water to render it flexible.

UNITED STATES PATENT OFFIC HENRY W. MORROVV, OF WILMINGTON, DELAVARE.

METHOD OF TREATING VULCANIZED FIBER.

SPECIFICATION forming part of Letters Patent No. 366,341, dated July 12, 1887.

Application filed October 13, 1884. Serial No.1 l5Al4. (No specimens.)

To all whom it may concern:

Be it known that I, HENRY W. MoRRoW, a citizen of the United States, and a resident of Wilmington, Delaware, have invented a cer tain Improved Method of Treating Vulcanized Fiber and Like Material, of which the following is a specification.

In many of the uses to which vulcanized fiber, gelatinized fiber, leatheroid, vegetable fiber which has been treated by the wellknown sulphuric-acid process, and like materials, are applied, it is desirable that the material should possess more or less softness or flexibility and that this quality should be lasting. For instance, when the material is used for many kinds of packings, washers, 850., flexibility is required, and it is important that the material should not become dry and hard with age, but should retain its flexibility as long as possible. I impart this permanent flexibility and softness to the material by subjecting it to a bath of deliquescent salt subsequent to the organic change produced in the vegetable fiber during its manufacture.

When vulcanized fiber is manufactured by treating the vegetable fiber or cellulose either with mother-water resulting from the manufacture of chloride of zinc or other chlorides,

or with a solution of chloride of zinc or other chloride, this active agent for producing the organic change in the cellulose to convert it into vulcanized fiber is thoroughly washed out of the fiber, thc latter being sometimes treated with a bath of water and glycerine or It has been suggested that when a soft product is desired comparatively little of the solution be washed out. This manner of producing flexible fiber is objectionable for various reasons, and principally because of the great diiiiculty or practical impossibility of so washinga batch of the material as to produce uniform flexibility throughout the whole batch.

In my improved process the vegetable fiber or cellulose after having been treated with the active agent, whatever it may be, to produce the required organic change, is preferably then thoroughly washed, and afterward subjected to a bath of a solution of deliquescent salt of a definite and known strength. The deliquescent salt may be used either alone, or a bath composed of a solution in water of deliqnescent salt and glycerine or saccharine matter may be used.

In carrying out my in,vention I preferably.

take the fiber as it comes from the cleansingbath, While yet soft and saturated with moisture, and place it in a bath consisting of a solution in water of some deliquescent salt or salts, which bath may be of a strength of from 14 to 30 Baume, (more or less, according to the degree of flexibility it is desired to impart.) When the deliquescent salt is used in solution with the addition of glycerine or saccharine matter, I preferably take a solution. of either or both of the latter of from 18 to 30 Baum, (more or less,) and add to it from thirty to sixty per cent. in bulk of the solution of deliquescent salt at a strength of about 30 Baum, (more or less.) As before remarked, these proportions and gravities may be changed according to the amount of softness and flexibility desired, the rule being that the stronger the solution the more flexible will be the product.

While I prefer to take the material as it comes from the cleansing-bath and subjectit to the softeningbaths described, I may treat the dried fiber in the same way. Of course, however, in that case the fiber would have to be immersed in the solution for a much greater length of time. The wet fiber as it comes from the bath may be immersed in the softening-solution for from five to fifty hours, the length of time depending upon the thickness or size of the mass immersed and the amount of softness to be imparted to it.

Good results may be had in some cases by omitting the cleansing bath and taking. the material directly from the bath of the active agent and immersing it in a bath of definite strength of solution of deliquescent salt, or of deliquescent salt and glycerine or saccharine matter, or both.

The softeningbath should be kept as nearly neutral as possible, and it should be stirred or agitated from time to time to prevent the heavier portions from settling and maintain as nearly as possible a uniform strength in all parts of the bath.

It is preferable to maintain the bath at about blood heat, as this serves tofacilitate the process.

As the strength of the bath is definite and all portions of the fiber subjected to its action are uniformly saturated with the solution, it follows that the product will be likewise uniform as regards its softness and flexibility.

The use of the glycerine or saccharine mat ter, or both, in the bath serves to render the product tougher, and such use is therefore preferred.

Chloride of calcium is the salt which is pre ferred on account of its cheapness and ease of manufacture; but I have used chlorides of zinc, tin, and other deliquescent chlorides or salts singly and in combination with good effect, the salt in the fiber absorbing and retaining sufficient moisture to keep the said fiber soft and flexible.

Chloride of sodium should be avoided, as material treated with a solution of this salt has a tendency to cause rust on metallic articles with which it is brought into contact.

When the fiberis treated as above explained, the softening-bath is reduced in strength either by the weaker solution employed as the active agent in effecting the organic change in the fiber or by the water contained in the fiber, if the latter has been cleansed prior to treatment in the softening-bath. In either case the softening-bath may after the treatment be restored to proper strength by evaporation of the surplus water, so as to prevent any waste.

The material after treatment in the manner set forth is, by preference, dried, in order to toughen and shrink it, and the desired articles of manufacture are cut or punched therefrom while it is in this dry condition, so that there is less liability of the said articles shrinking than there would be if they were cut from the material while the latter was wet.

I am aware that in the patent of Andrew Van Bibber (No. 113,224) chloride of calcium mixed with acomposition for printers inking rollers has been suggested as a means of rendering the rollers soft and flexible.

I claim as my invention- 1. The method of treating vulcanized fiber and like material to impart softness and flexibility thereto, which consists in taking the fiber after the organic change therein has been produced in the process of manufacture and subjecting said fiber to a bath of a solution of deliquescent salt, asdescribed.

2. The method of treating vulcanized fiber and like material to impart softness and flexibilility thereto, which consists in subjecting the fiber to a bath of a solution of deliquescent salt after said fiber has undergone organic change and cleansing in the process of manufacture, as described.

3. The method of treating vulcanized fiber and like material,which consists in taking the vulcanized fiber after the organic change therein has been produced in the process of manufacture and subjecting it to a bath of a solution of deliquescent salt combined with glycerine or saccharine matter, or both, as described.

4. The herein-described bath for softening vulcanized fiber and like material, said bath consisting of a solution of deliquescent salt and glycerine or saccharine matter, or both, as set forth.

5. The method'of treating vulcanized fiber and like material to impart softness and flexibility thereto, which consists in taking the fiber after the organic change therein has been produced in the process of manufacture and subjecting it to a softening-bath of a solution of chloride of calcium.

6. The method of treating vulcanized fiber and like material to impart softness and flexibility thereto, which consists in taking the fiber after the organic change therein has been produced in the process of manufacture and subjecting it to a softening-bath of a solution ofchloride of calcium combined with glycerine or saccharinematter.

7. The method of treating vulcanized fiber and like material to impart softness and flexibility thereto, which consists in subjecting the fiber to a softening-bath of a solution of chlo ride of calcium after said fiber has undergone organic change and subsequent cleansing in the process of manufacture, as described.

8. The method of treating vulcanized fiber and like material to impart softness and flexibility thereto,which consists in subjecting the fiber to a softening-bath of a solution of chloride of calcium combined with glycerine or saccharine matter, or both, after said fiber has undergone organic change and subsequent cleansing in the process of manufacture, as described.

9. The herein-described bath for softening vulcanized fiber and like material, said bath consisting of a solution of chloride of calcium and saccharine matter or glycerine, or both, substantially as set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

HENRY W. MORROW. Witnesses:

J our: M. CLAAYTON, HARRY SMITH. 

